The review of Kumari et al. [1], titled “Emerging Influenza D Virus Threat: What We Know so Far!”, deals with an important issue, although it is not well defined: what we know about the emerging Influenza D virus (IDV). Many congratulations to the authors for putting the focus on such an important and topical subject, but this is not yet fully understood. In this review, the evolution, epidemiology, virology and pathobiology of IDV and the possibility of transmission among various hosts and potential to cause human disease is thoroughly analyzed. Kumari and coworkers, underlined that despite strong results achieved by a considerable number of experimental, epidemiological and serological studies, current knowledge of IDV, a new member of the Orthomyxoviridae family, is still limited, especially concerning the evidence that Koch’s postulates are fulfilled for this agent.